Unreal Engine Issues
Unreal Engine Issues
Error on Loading Pawn Blueprint Containing ActorSequenceComponent from GameMode Constructor
UE - Anim - Sequencer - Oct 25, 2017When attempting to load a Blueprint that contains a ActorSequence component from inside of a Gamemode's constructor, errors are given. The ActorSequence component is also removed from the Blueprint ...
ProxyLOD plugin generates uninitialized vertices at end of a vertex buffer
UE - World Creation - Worldbuilding Tools - HLOD - Sep 11, 2020ProxyLOD::FQuadricMeshSimplifier::OutputMesh may remove duped verts. The input vertex buffer was resized by numVerts from FQuadricMeshSimplifier before calling OutputMesh. So these behaviors genera ...
UMG: Drag-drop widgets get stuck at (0, 0)
UE - Editor - UI Systems - UMG - Nov 7, 2022Reported on the dev forum, drag-drop widget is broken in the 5.1 Preview.https://forums.unrealengine.com/t/unreal-engine-5-1-preview/662523/221 Anyone else having problems with UUserWidget::SetPosi ...
Missing PSO Precaches in the engine
UE - Rendering - Architecture - RHI - Aug 20, 2025A licensee wanted to report some missing PSO Precaching they found, which they have fixed locally: 1. UCableComponent doesn't implement CollectPSOPrecacheData or call CheckPSOPrecachingAndBoostPri ...
FPS Perf Regression on 980
UE - Graphics Features - Mar 17, 2015At least one user has so far reported a noticeable drop in FPS from 4.6.1 to 4.7.2 in a heavy scene; using a GTX 980. I've reproduced a perf drop in a cooked 4.7 build of elemental demo compared to ...
UK2Node_EnumLiteral always outputs defaulted (0) value if input pin is connected
UE - Gameplay - Blueprint - Sep 28, 2018The reported behavior repros in 4.20 and 4.21, but does not repro in 4.19. Regarding the "Literal Enum" node in blueprints: When an input enum value is connected to the input pin, the output is al ...
CLion cannot update CMake for an Unreal Studio project created on a drive other than the one the Engine is installed on
UE - Foundation - Cpp Tools - Apr 22, 2019If an Unreal Studio project is created on a different drive from where the Engine is installed, CLion is unable to successfully update CMake. The location for where Engine files can be found appears ...
Lighting channels not working as expected when enabling Ray Tracing Shadow
UE - Graphics Features - Lumen - Oct 13, 2020Non-Ray Tracing Shadows are only cast from lights on meshes assigned to the same Lighting Channel. When enabling Ray Tracing Shadows this is not the case. Lights will still cast Ray Tracing Shadows ...
Variant manager crash in UPropertyValue::HasValidResolve
UE - Editor - Content Pipeline - Variants - Nov 21, 2024in the past we have reported a lot of VM related bugs which got fixed over time. Unfortunately, I think we have another one. Right now we're using 5.0.3 binaries from the launcher. Now the pro ...
Multiple setter functions in UMaterialEditingLibrary always return false even when the parameter is correctly set on the MaterialInstance.
UE - Rendering - Architecture - Materials - May 30, 2025In Unreal Engine, materials can expose parameters that can then be modified via instances (MaterialInstanceConstant). The UMaterialEditingLibrary provides several functions to modify these parameter ...